Development of ex situ normothermic reperfusion as an innovative method to assess pancreases after preservation

Static cold storage (SCS) is the standard method for pancreas preservation prior to transplantation; however, it does not permit organ assessment. Normothermic reperfusion (NR) is utilized clinically for other organs to assess viability. Our aim was to develop NR using normothermic machine perfusion technique to simulate reperfusion at the time of transplantation, enabling evaluation of oxygenated hypothermic machine perfusion (HMPO2) as a newer strategy to optimize pancreas preservation. 13 porcine pancreases procured after circulatory death were divided into 3 groups: 4 pancreases preserved using SCS, and 2 groups preserved by HMPO2 (n = 4 and n = 5, differing by type of preservation solution). Duration of perfusion or cold storage was 6 hours before the 1-hour assessment using NR. Outcome measures were perfusion characteristics, biochemistry and change in tissue water mass as oedema assessment. During NR, the HMPO2 groups demonstrated better perfusion characteristics, normal macroscopic appearances, decreased water mass and one HMPO2 group demonstrated a response to glucose stimulation. Conversely, the SCS group showed an increased water mass and developed early macroscopic appearances of oedema, interstitial haemorrhage and minimal portal outflow. This study suggests that ex situ assessment of pancreases by NR is promising, and that HMPO2 may be better than SCS.

European contribution to the study of ROS: A summary of the findings and prospects for the future from the COST action BM1203 (EU-ROS)

The European Cooperation in Science and Technology (COST) provides an ideal framework to establish multi-disciplinary research networks. COST Action BM1203 (EU-ROS) represents a consortium of researchers from different disciplines who are dedicated to providing new insights and tools for better understanding redox biology and medicine and, in the long run, to finding new therapeutic strategies to target dysregulated redox processes in various diseases. This report highlights the major achievements of EU-ROS as well as research updates and new perspectives arising from its members. The EU-ROS consortium comprised more than 140 active members who worked together for four years on the topics briefly described below. The formation of reactive oxygen and nitrogen species (RONS) is an established hallmark of our aerobic environment and metabolism but RONS also act as messengers via redox regulation of essential cellular processes. The fact that many diseases have been found to be associated with oxidative stress established the theory of oxidative stress as a trigger of diseases that can be corrected by antioxidant therapy. However, while experimental studies support this thesis, clinical studies still generate controversial results, due to complex pathophysiology of oxidative stress in humans. For future improvement of antioxidant therapy and better understanding of redox-associated disease progression detailed knowledge on the sources and targets of RONS formation and discrimination of their detrimental or beneficial roles is required. In order to advance this important area of biology and medicine, highly synergistic approaches combining a variety of diverse and contrasting disciplines are needed.

A semiparametric graphical modelling approach for large-scale equity selection

We propose a new stock selection strategy that exploits rebalancing returns and improves portfolio performance. To effectively harvest rebalancing gains, we apply ideas from elliptical-copula graphical modelling and stability inference to select stocks that are as independent as possible. The proposed elliptical-copula graphical model has a latent Gaussian representation; its structure can be effectively inferred using the regularized rank-based estimators. The resulting algorithm is computationally efficient and scales to large data-sets. To show the efficacy of the proposed method, we apply it to conduct equity selection based on a 16-year health care stock data-set and a large 34-year stock data-set. Empirical tests show that the proposed method is superior to alternative strategies including a principal component analysis-based approach and the classical Markowitz strategy based on the traditional buy-and-hold assumption.

Management of uncomplicated acute diverticulitis: results of a survey

PURPOSE

A survey was conducted to document current medical treatment of patients with uncomplicated acute diverticulitis.

METHODS

A survey was mailed to 667 fellows of The American Society of Colon and Rectal Surgeons certified by the American Board of Colon and Rectal Surgery. Queries were based on a clinical scenario of a patient with uncomplicated diverticulitis.

RESULTS

Three hundred seventy-three surveys (56 percent) were returned completed. The majority (66 percent) chose an abdominal computed tomographic scan as the initial diagnostic test. One-half used a single intravenous antibiotic with second-generation cephalosporins (27 percent) and ampicillin/sulbactam (16 percent) being the most common. Oral antibiotics given at discharge were ciprofloxacin (18 percent), amoxicillin/clavulanate (14 percent), metronidazole (7 percent), and doxycycline (6 percent). Combinations chosen were ciprofloxacin/metronidazole (28 percent) and metronidazole/trimethoprim sulfamethoxazole (6 percent), whereas 21 percent chose a variety of other antibiotics. The majority (74 percent) prescribed oral antibiotics for 7 to 10 days. Dietary recommendations at discharge were low residue (68 percent), regular (21 percent), and high residue (10 percent). Half of those surveyed believed avoidance of seeds and nuts were of no value. Follow-up examinations chosen included sigmoidoscopy and barium enema (29 percent), colonoscopy (25 percent), sigmoidoscopy (17 percent), barium enema (13 percent), and other (16 percent). Sixty-five percent of colon and rectal surgeons claim to handle more than half of their patients with uncomplicated diverticulitis on an outpatient basis.

CONCLUSION

Variations in the management of uncomplicated sigmoid diverticulitis are noted among colon and rectal surgeons, especially in terms of antibiotic choice, discharge instructions, and follow-up outpatient studies. The survey results are compared with the conclusions reached in The American Society of Colon and Rectal Surgeons practice parameters. Documentation of practice pattern variation may serve as an educational tool for physicians to improve their quality and cost of medical care. Consideration should be given to better publicize already existing American Society of Colon and Rectal Surgeons practice parameters for this common entity.

Acute pyelonephritis in pregnancy

There were 107 episodes of pyelonephritis associated with pregnancy or the early puerperium occurring in 103 gravidas investigated retrospectively for information concerning prematurity, low birthweight, and antibiotic susceptibility patterns in the recovered microorganisms. No difference was found in the incidence of prematurity on low birthweight between that group and a control group of gravidas from the same population. Members of the Enterobacteriaceae genus were the most common bacterial isolates from the urine, with a large portion of E. coli being resistant to both ampicillin (33%) and cephalothin (13%). Treated pyelonephritis associated with pregnancy does not appear to predispose to prematurity or low birthweight in this population. Also, initial therapy with a first-generation cephalosporin may no longer be appropriate, because a significant number of isolates (11%) were resistant to cephalothin.